The development of a train schedule for a global rail network, i.e., nationwide, is difficult on a real time basis due to the complexity of the problem of controlling many trains competing for limited resources simultaneously. Rail networks typically contain tens of thousands of miles of track, thousands of locomotives and hundreds of thousands of freight cars. At any one moment, thousands of trains and maintenance vehicles may be competing for a limited amount of track. To manage consistent scheduled service in this environment, railroads use the “divide and conquer” technique to partition the railroad network into several control territories and generate a local movement plan for each control territory to thereby distribute the complexity of the scheduling problem over many scheduling resources. Human train dispatchers are assigned to these control territories, and have the responsibility to smoothly transit trains and equipment across the control territory, with minimum delay in accordance with the corresponding movement plan for the control territory. Multiple dispatchers, each controlling a predefined portion of the railroad, comprise the paradigm for modern day computer-based railroad dispatching systems.
In this environment, the dispatcher is expected to solve complex movement problems in real time. For example, dispatchers must consider the limited track resources, length of trains, length of available sidings, train meet and pass points, maintenance requests for track time, engine availability, etc. Dispatching can become a stressful environment, and while safeguards are in place with signaling systems in the field, dispatcher mistakes could cost lives and frequently results in significant decreases in performance for the railroad To ease the burden, computer processing scheduling systems are used to help dispatchers “see” their control area, and external systems provide a constant flow of information about the state of the railroad. This information flow includes train schedules, customer commitments, maintenance schedules, train consists, track outages, crew information, weather and other dynamic factors that directly affect the daily operations of the railroad. As more systems are computerized, dispatchers receive more accurate information, however; the volume of information is growing at a rate that makes it increasingly difficult to formulate decisions and actions in real time. Because of information overload, and the decision structures of typical dispatch systems, dispatchers lack insight into effects of their actions on the entire route of the train, or the effects to the railroad as a whole. Several train dispatchers will “touch” a train as it traverses its route across the railroad network. With limited information and a predefined decision structure, it is inevitable that one dispatcher's action, while appropriate within the context of the dispatcher's territory, results in large financial losses for the railroad.
Without full comprehension of the complex adjacent territories or the relative value of a train to the railroad at any one particular instant, the dispatcher is ill equipped to make optimum dispatch decisions, even within their control own territory. As such, a dispatcher may route a train into an adjacent territory, only to discover that by doing so, the end result is more congestion for the overall railroad. In this instance the correct decision would have been to hold the train within the dispatcher's territory at an available siding or yard with ample capacity, and wait until the congestion reduces or clears. Another situation in which the dispatcher lacks adequate information about the global network to make the most optimal decision may occur where several trains need to pass through a congested track area, and there is not enough available track to accommodate all simultaneously. The dispatcher has to quickly decide which trains to “side” (place in an available siding) in order to let other trains pass. In today's dispatching environments, there is insufficient information about a train in context with all other trains in other control territories in order for the dispatcher to make the best decision for the railroad as a whole, due to the lack of coordination of the movement of trains from one control territory to an adjacent control territory.
The present application is directed to a system and method of scheduling and controlling the movement of trains over a large rail network. According to one aspect of the invention, the rail network is divided into a plurality of planning areas as a function of the shared resources between each adjacent planning area.
According to another aspect of the present invention, a local movement plan for each planning area develops a local movement plan independently of the movement plan developed for other planning areas to control the movement of trains into and out of the shared resources associated with the adjacent planning areas.
According to yet another aspect of the present invention, each of the local movement plans is evaluated to identify conflicts at the shared resources between adjacent planning areas.
According to still another aspect of the present invention, the local movement plans are modified to resolve the identified conflicts at the boundary elements.
The advantages of the present invention will be readily apparent to one skilled in the art to which it pertains from a perusal of the claims, the appended drawings, and the following detailed description.